Which is a patient factor that influences heat and cold emergencies?

• A. Environmental conditions
• B. Time of day
• C. Humidity
• D. Age

Answer: (D)

Age as a patient factor matters because how the body handles extreme temperatures changes with age. Thermoregulation isn’t the same from infancy through old age, so a person’s age directly affects their risk for heat and cold emergencies. Infants and young children have a higher surface-area-to-body-mass ratio and immature cooling and warming mechanisms, so they can gain heat quickly or lose heat rapidly, making them especially vulnerable. Older adults often have reduced sweating, diminished vasomotor responses, thinner skin, and common chronic illnesses or medications that blunt the body's ability to adapt to heat or cold, increasing the risk of heat-related illness and hypothermia.

Environmental conditions, humidity, and time of day influence risk by changing the external environment, but they don’t reflect the person’s inherent susceptibility the way age does.